U.S. patent number 5,248,272 [Application Number 07/844,163] was granted by the patent office on 1993-09-28 for forwards facing rowing apparatus with feathering of the oar blades.
Invention is credited to Stephen duPont.
United States Patent |
5,248,272 |
duPont |
September 28, 1993 |
Forwards facing rowing apparatus with feathering of the oar
blades
Abstract
A forwards facing rowing apparatus wherein the usual pair of
sweep hinges is replaced by a single, common axis, sweep hinge
system mounted to and rockable with the oarlock mainframe and
wherein a blade feathering mechanism including a coupling device
such as a pair of swing gears is employed at the oarset including a
handle loom and a blade loom, one of the gears being driven from a
rotating handle at the in-board end of the handle loom while the
mating gear drives or rotates the blade at the outer end of the
blade loom. Each gear may be affixed to a rotatable member such as
a torque shaft extending along the handle and blade looms and
connected at opposite ends to both the handle and blade,
respectively. Alternatively, the handle and blade looms may be
rotatable members and one of the pair of gears may be attached to
each member. The swing gears are arranged to mesh with one another
with the generally vertical tangent line of meshing of the gear
pitch circles being aligned with the single common sweep hinge
axis, allowing the gears to remain in mesh regardless of the large
and rapid changes in sweep angularity occurring between the handle
and blade looms and also reversing the rotation of feathering at
the blade from that at the handle. A linkage assembly is also
provided for synchronizing the motion of the handle and blade looms
whereby the blade loom is constrained to move in the same direction
as that of said handle loom when the handle loom is rotated about
the common sweep axis.
Inventors: |
duPont; Stephen (Osprey,
FL) |
Family
ID: |
25291992 |
Appl.
No.: |
07/844,163 |
Filed: |
March 2, 1992 |
Current U.S.
Class: |
440/103;
440/105 |
Current CPC
Class: |
B63H
16/102 (20130101) |
Current International
Class: |
B63H
16/00 (20060101); B63H 16/10 (20060101); B63H
016/04 () |
Field of
Search: |
;440/102,103
;416/74 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Sotelo; Jesus D.
Attorney, Agent or Firm: Doherty; John R.
Claims
What is claimed is:
1. A forwards facing rowing apparatus comprising, in combination: a
boat having an elongated hull with fore and aft ends, an outrigger
projecting laterally outward from one side of said hull and an
oarloom assembly mounted to said outrigger, said oarloom assembly
comprising a handle loom having an inboard end and an outboard end,
a handle rotatable about the handle loom located at said inboard
end of said handle loom, a blade loom extending outwardly from said
outrigger and having an inner end and an outer end, a blade located
at said outer end of said blade loom, an oarlock mainframe
hingeably mounted to said outrigger for rotation about an axis
orientated generally fore and aft of said hull, a first sweep hinge
member affixed to the outboard end of said handle loom, a second
sweep hinge member affixed to the inner end of said blade loom,
means for mounting said first and second sweep hinge members on
said oarlock mainframe for rotation about a common sweep axis
orientated in a generally perpendicular relationship with respect
to said axis of rotation of said mainframe, linkage means connected
to said handle loom and said blade loom for synchronizing the
motion of said blade loom with that of said handle loom whereby
said blade loom is constrained to move in the same direction as
that of said handle loom when said handle loom is rotated about
said common sweep axis and blade feathering means associated with
both said handle loom and said blade loom for changing the angle of
incidence of said blade with respect to the surface of the water
floating said hull when said handle is rotated.
2. A rowing apparatus according to claim 1, wherein both said
handle loom and said blade loom are non-rotatable members and
wherein said blade feathering means includes a first rotatable
member connected to said handle and extending along said
non-rotatable handle loom, a second rotatable member connected to
said blade and extending along said non-rotatable blade loom and a
coupling device connecting said rotatable members for transmitting
torque and rotary motion therebetween.
3. A rowing apparatus according to claim 2, wherein said first and
second rotatable members are elongated torque shafts mounted
coaxially within said handle loom and said blade loom.
4. A rowing apparatus according to claim 2, wherein said first and
second rotatable members are elongated torque shafts mounted
externally along side said handle loom and said blade loom.
5. A rowing apparatus according to any one of claims 2, 3 and 4,
wherein said linkage means comprises a first link rod hingeably
connected to one of said non-rotatable members, a second link rod
hingeably connected to the other of said non-rotatable members,
said first and second link rods being hingeably connected to one
another at a common hinge point remote from said handle loom and
said blade loom and a third link rod hingeably connected to at
least one of said first or second link rods and to said hull or
outrigger.
6. A rowing apparatus according to claim 5, wherein said first and
second link rods are hingeably connected to said non-rotatable
members at substantially equi-distant lengths from said common
sweep hinge axis.
7. A rowing apparatus according to claim 5, wherein said first and
second link rods are hingeably connected to said non-rotatable
members at different lengths from said common sweep hinge axis.
8. A rowing apparatus according to claim 5, wherein said first link
rod is hingeably connected to said non-rotatable member on the fore
or aft side of said handle loom and wherein said second link rod is
hingeable connected to the other of said non-rotatable members on
an opposite side of said blade loom.
9. A rowing apparatus according to claim 8, wherein said first and
second link rods are hingeably connected to said non-rotatable
members by means of bi-directional hinge pin assemblies.
10. A rowing apparatus according to claim 5, wherein said third
link rod is hingeably connected to at least one of said first and
second link rods and to said hull or outrigger by means of
universal hinge pin assemblies.
11. A rowing apparatus according to any one of claims 2, 3 and 4,
wherein said linkage means comprises a first link rod hingeably
connected to one of said non-rotatable members, a second link rod
hingeably connected to the other of said non-rotatable members,
said first and second link rods being hingeably connected to a
slider, said slider being moveable along a fixed track orientated
generally fore and aft of said hull.
12. A rowing apparatus according to claim 11, wherein said track is
affixed to said oarlock mainframe.
13. A rowing apparatus according to claim 11, wherein said first
and second link rods are hingeably connected to said non-rotatable
members at substantially equi-distant lengths from said common
sweep hinge axis.
14. A rowing apparatus according to claim 11, wherein said first
and second link rods are hingeably connected to said non-rotatable
members at different lengths from said common sweep hinge axis.
15. A rowing apparatus according to any one of claims 2, 3 and 4,
wherein said coupling device means comprises a pair of swing gears
one of each of which is connected to one of said rotatable members,
said swing gears being arranged to engage one another with the
tangent line of the gear pitch circle of each gear substantially
aligned with said common sweep hinge axis.
16. A rowing apparatus according to claim 15, wherein each of said
swing gears is approximately a quarter sector of a full gear circle
leaving space for receiving a part of the rotatable member of a
mating gear thereby increasing the sweep angle of both said handle
loom and said blade loom.
17. A rowing apparatus according to any one of claims 2, 3 and 4,
wherein said coupling device comprises a universal joint having a
first yoke member connected to one of said rotatable members and a
second yoke member connected to the other of said rotatable
members, a hinge block disposed between said first and second yoke
members and a pair of hinge pins extending through said hinge block
at substantially right angles to one another, one of said hinge
pins extending through said first yoke member and the other of said
hinge pins extending through said second yoke member.
18. A rowing apparatus according to any one of claims 2, 3 and 4,
wherein said coupling device comprises a pair of universal joints
each including a first yoke connected to one of said rotatable
members and a second yoke connected to said first yoke by a hinge
block and hinge pins, the second yoke of one of said pairs of
universal joints having a hollow end while the second yoke of the
other of said pairs of universal joints having an end of lesser
diameter than said hollow end, said end of lesser diameter slidably
fitting inside said hollow end forming a splined slip joint.
19. A rowing apparatus according to any one of claims 2, 3 and 4,
wherein said coupling device comprises a linkage assembly composed
of a rocker arm pivoted at its center and having opposite ends, a
first lever connected at one end to one of said rotatable members,
a second lever connected at one end to the other of said rotatable
members, a first link rod connected to the other end of said first
lever and to an opposite end of said rocker arm and a second link
rod connected to the other end of said second lever and to the
other opposite end of said rocker arm.
20. A rowing apparatus according to claim 19, wherein said rocker
arm is pivotally mounted to a hinge pin connecting said sweep hinge
members to said oarlock mainframe along said common sweep axis.
21. A rowing apparatus according to any one of claims 2, 3 and 4,
wherein said coupling device comprises a push pull assembly
composed of a first lever connected at one end to one of said
rotatable members, a second lever connected at one end to the other
of said rotatable members, a push pull wire enclosed in an outer
flexible casing, said wire having one end connected to the other
end of said first lever and its other end connected to the other
end of said second lever, and means for securing said outer casing
against axial movement along said wire.
22. A rowing apparatus according to claim 1, wherein both said
handle loom and said blade loom are rotatable members, said
rotatable handle loom being connected to said handle and being
supported within a first non-rotatable member and said rotatable
blade loom being connected to said blade and being supported by a
second non-rotatable member, and wherein said blade feathering
means includes a coupling device connecting said rotatable handle
loom and said rotatable blade loom for transmitting torque and
rotary motion therebetween.
23. A rowing apparatus according to claim 1, wherein one of said
handle loom and said blade loom is a rotatable member and the other
of said handle blade loom is a non-rotatable member, said one of
said rotatable handle loom and said blade loom being connected to
one of said handle and said blade and being supported by another
non-rotatable member and wherein said blade feathering means
includes another rotatable member connected to the other of said
handle and said blade and extending along the other of said
non-rotatable handle loom and said blade loom and a coupling device
connecting said one of said rotatable handle loom and said blade
loom and said other rotatable member for transmitting torque
therebetween.
24. A rowing apparatus according to claim 3 or 4, wherein at least
one of said non-rotatable members is a tubular casing including
bearing means for rotatably supporting at least one of said handle
loom and said blade loom.
25. A rowing apparatus according to claim 24, wherein said tubular
casing is shorter in length than at least said blade loom.
26. A rowing apparatus according to claim 24, wherein said tubular
casing has first and second interior surfaces and wherein said
rotatable handle loom is provided with at least one exterior
surface adapted to engage said first and said second interior
surfaces on said tubular casing when said handle loom is rotated,
the arrangement being such that said blade is orientated in a plane
substantially parallel to the surface of the water when said handle
loom is rotated to engage said exterior surface with one of said
interior surfaces on said tubular casing and in a plane
substantially normal to the surface of the water when said handle
loom is rotated to engage said exterior surface with the other of
said interior surfaces.
27. A rowing apparatus according to claim 26, wherein said
rotatable handle loom is formed with an annular embossment and
wherein said exterior surface is a substantially flat surface on
said embossment.
28. A rowing apparatus according to claim 26, wherein said
rotatable handle loom is connected to one end of an extension shaft
rotatably supported within said bearing means by a universal joint,
the other end of said shaft being connected to said coupling
device.
29. A forwards facing rowing apparatus comprising, in combination:
a boat having an elongated hull with fore and aft ends, an
outrigger projecting laterally outward from one side of said hull
and an oarloom assembly mounted to said outrigger, said oarloom
assembly comprising a non-rotatable handle loom having an inboard
end and an outboard end, a handle located at said inboard end of
said handle loom, a non-rotatable blade loom extending outwardly
from said outrigger and having an inner end and an outer end, a
blade located at said outer end of said blade loom, an oarlock
mainframe hingeably mounted to said outrigger for rotation about an
axis orientated generally fore and aft of said hull, a first sweep
hinge member affixed to the outboard end of said handle loom, a
second sweep hinge member affixed to the inner end of said blade
loom, means for mounting said first and second sweep hinge members
for rotation about a common sweep axis extending through said
oarlock mainframe and orientated in a generally perpendicular
relationship with respect to said axis of rotation of said
mainframe, linkage means connected to said non-rotatable handle
loom and blade loom for synchronizing the motion of said blade loom
with that of said handle loom whereby said blade loom is
constrained to move in the same direction as that of said handle
loom when said handle loom is rotated about said common sweep axis,
a first torque shaft connected to said handle and extending along
said handle loom, a second torque shaft connected to said blade and
extending along said blade loom, and a pair of swing gears one of
each of which is connected to said first and second torque shafts,
said swing gears being arranged to engage one another with the
tangent line of the gear pitch circle of each gear substantially
aligned with said common sweep hinge axis, the arrangement being
such that when said handle is rotated said blade is rotated in a
reverse direction thereby changing the angle of incidence of said
blade with respect to the surface of the water floating said
hull.
30. A rowing apparatus according to claim 29, wherein said first
and second torque shafts are mounted coaxially within said handle
loom and said blade loom.
31. A rowing apparatus according to claim 29, wherein said linkage
means comprises a first link rod hingeably connected to said
non-rotatable handle loom, a second link rod hingeably connected to
said non-rotatable blade loom, said first and second link rods
being hingeably connected to one another at a common hinge point
remote from said handle loom and said blade loom and a third link
rod hingeably connected to at least one of said first or second
link rods and to said hull or outrigger.
32. A rowing apparatus according to claim 29, wherein said linkage
means comprises a first link rod hingeably connected to said
non-rotatable handle loom, a second link rod hingeably connected to
said non-rotatable blade loom, said first and second link rods
being hingeably connected to a slider, said slider being moveable
along a fixed track orientated generally fore and aft of said
hull.
33. A forwards facing rowing apparatus comprising, in combination:
a boat having an elongated hull with fore and aft ends, an
outrigger projecting laterally outward from one side of said hull
and an oarloom assembly mounted to said outrigger, said oarloom
assembly comprising a handle loom having an inboard end and an
outboard end, a handle affixed to said inboard end of said handle
loom, a blade loom extending outwardly from said outrigger and
having an inner end and an outer end, a blade affixed to said outer
end of said blade loom, said handle loom being rotatably mounted
within a first non-rotatable member and said blade loom being
rotatably mounted within a second non-rotatable member, an oarlock
mainframe hingeably mounted to said outrigger for rotation about an
axis orientated generally fore and aft of said hull, a first sweep
hinge member affixed to said first non-rotatable member, a second
sweep hinge member affixed to said second non-rotatable member,
means for mounting said first and second sweep hinge members for
rotation about a common sweep axis extending through said oarlock
mainframe and orientated in a generally perpendicular relationship
with respect to said axis of rotation of said mainframe, linkage
means connected to said first and second non-rotatable members for
synchronizing the motion of said blade loom with that of said
handle loom whereby said blade loom is constrained to move in the
same direction as that of said handle loom when said handle loom is
rotated about said common sweep axis, and a pair of swing gears one
of each of which is connected to said handle loom and said blade
loom, said swing gears being arranged to engage one another with
the tangent line of the gear pitch circle of each gear
substantially aligned with said common sweep hinge axis, the
arrangement being such that when said handle is rotated said blade
is rotated in a reverse direction thereby changing the angle of
incidence of said blade with respect to the surface of the water
floating said hull.
34. A rowing apparatus according to claim 33, wherein said first
and second non-rotatable members are tubular casings including
bearing means for rotatably supporting said handle loom and said
blade loom.
35. A rowing apparatus according to claim 33, wherein said linkage
means comprises a first link rod hingeably connected to said first
non-rotatable member, a second link rod hingeably connected to said
second non-rotatable member, said first and second link rods being
hingeably connected to one another at a common hinge point remote
from said handle loom and said blade loom and a third link rod
hingeably connected to at least one of said first or second link
rods and to said hull or outrigger.
36. A rowing apparatus according to claim 33, wherein said linkage
means comprises a first link rod hingeably connected to said first
non-rotatable member, a second link rod hingeably connected to said
second non-rotatable member, said first and second link rods being
hingeably connected to a slider, said slider being moveable along a
fixed track orientated generally fore and aft of said hull.
Description
BACKGROUND OF THE INVENTION
This invention relates to forwards facing rowing in general. More
particularly, the invention relates to a forwards facing rowing
apparatus having structurally separate handle and blade looms
rotatable about a common sweep hinge axis and including a device
for feathering the oar blades during the return stroke of the
oarlooms.
Forwards facing rowing apparatus have been known for many years
now. Such apparatus have universally employed two oar sections
consisting of a handle loom and a structurally separate blade loom.
The handle and blade looms have always been hinged at the oarlock
mainframe, each by a separate generally vertical sweep hinge, the
blade loom being constrained to move backwards when the handle loom
moves backwards and forwards when the handle moves forwards, thus
allowing forwards facing of the oarsman. This synchronized motion
of the two oar looms has been achieved by using a slaving linkage
such as crossover link rods, a pair of gear sectors, drums and
cables or, in some cases, sprockets and chains, to interconnect the
two oar loom sections. The oarlock mainframe is usually mounted to
a horizontal teeter hinge that is oriented generally fore and aft
to the centerline of the boat hull to permit raising and lowering
the paddle or blade to the water. This rather complex articulated
system is very poorly adapted to feathering the oar blades by
twisting the handles at each end of the handle looms, which has
always been a requirement for high performance rowing in racing
shells.
The action of feathering consists of rotating the oar blades to
flatten them horizontally by turning the hand grips so that on the
return stroke of rowing, the plane of the blade will be
substantially parallel to the surface of the water. This reduces
wind resistance and also forces the blade, in the event it should
contact the water, to ride up on the surface and plane, rather than
dig in and sink, thereby interrupting the smooth return stroke of
the rowing cycle.
When feathering in conventional rearwards facing rowing, the
oarsman is taught to lower his wrists to feather, which brings the
forwards moving top edge of the oar blade forwards, thereby
presenting the blade to the water surface in an upwards slanted
direction so as to ride over the surface. However, in forwards
facing rowing, the oarsman sits behind, rather than ahead, of the
oar handles which is the case in conventional rearwards facing
rowing, with the result that should he lower his wrists to feather,
the lower edge of the oar blade would proceed it and possibly hit
the water. This, of course, would bury the oar beneath the surface
of the water, completely disrupting the stroke of the oarsman and,
indeed, possibly breaking the oar or, even worse, injuring the
oarsman. The oarsman nevertheless has been trained by conventional
rowing to drop his wrists to feather the blades, this motion being
actually the best way to achieve feathering since the wrists will
again be straight for pulling the oarloom during the power stroke.
It is therefore highly desirable to rotate the handle grips in a
direction opposite to that of the blades in order to achieve
feathering in forwards facing rowing.
It is also desirable in forwards facing rowing that the feathering
mechanism have as little friction as possible. The oarsman is
holding the handles with his bare hands and his hands should not
become blistered or over fatigued by feathering. A further reason
for low friction is that the oars are usually feathered nearly
automatically from the resistance of the water when they are
reversed for the return stroke, and a low friction feathering force
is important in this function.
SUMMARY OF THE INVENTION
The invention is directed to an improved forwards facing rowing
apparatus which obviates many of the problems associated with
similar apparatus of the prior art. In this forwards facing rowing
apparatus, the usual pair of sweep hinges are replaced by a single
common axis, concentric sweep hinge system which is mounted to and
rockable with the oarlock mainframe. However, the single axis sweep
hinge system of the invention makes it possible to employ a variety
of feathering devices or mechanisms which are simple in
construction and operation as compared to the rather elaborate and
complex systems of the prior art. For example, in a preferred
embodiment of the invention, a pair of swing gears are employed in
conjunction with a non-rotatable handle and blade loom for
feathering the blades, one of the gears being driven from a
rotating handle at the opposite end of the handle loom while the
mating gear drives or rotates the blade at the opposite end of the
blade loom, each gear being affixed to a rotatable member, such as
a torque shaft, connected to the handle and blade, respectively.
The swing gears are orientated such that the generally vertical
tangent line of meshing of the gear pitch circles is aligned with
the single common sweep hinge axis. This allows the gears to remain
in mesh regardless of the large and rapid changes in angularity
that occur between the handle loom centerline and the blade loom
centerline during the motion of sweep action in rowing. Swing gears
are simple but very advantageous to use in the rowing apparatus
since they have very low friction and can accommodate large angle
changes between the axes of the gears. In addition, the single set
of swing gears reverses the rotation of feathering at the blade
from that at the handle which is, of course, very desirable in
forwards facing rowing.
Another advantage of the single common sweep hinge system of the
invention is the relative ease by which synchronization of the two
oarloom sections can be achieved. Thus, as a consequence of having
both the handle and blade looms pivoted about a single sweep axis,
a number of simple linkage system can be used such as link arms,
sprockets, chains, drums and cables or any other known linkage
system.
A preferred linkage system, however, consists of a pair of link
rods attached to the oarlooms and to one another at a common hinge
point. A third link rod lies traversely to the boat hull and is
connected to the common hinge point and to the hull or outrigger.
The third link rod can be replaced by a fore and aft slide track
and slider mounted to the oarlock mainframe. Thus, in either case,
when the handle loom is swept forward or aft, the blade loom is
constrained to move in the same direction which is required in
forwards facing rowing.
According to still another preferred embodiment of the invention, a
pair of swing gears are employed in conjunction with a rotatable
handle and blade loom for feathering the blades, one of the gears
being driven by rotating a handle affixed to the opposite end of
the handle loom, in this case, rotating both the handle loom and
the gear, while the mating gear drives the blade loom and the blade
affixed to its opposite end. Both the handle loom and the blade
loom are rotatably supported by non-rotatable members, such as
tubular casings, for example, having sweep hinge members attached
thereto for rotatably mounting both members about a common sweep
axis.
An important feature made possible by this preferred embodiment of
the invention is the provision of means for positively locating the
handle loom and, consequently, the rotatable blade loom and blade
during the rowing operation. The handle loom is located in either
one of two positions during the rowing cycle, namely, in a first
position corresponding to the power stroke when the blade is
orientated in a plane generally normal to the surface of the water
and, conversely, in a second position corresponding to the return
stroke when the blade is feathered in a plane generally parallel to
the surface of the water. This feature is achieved by providing a
surface on the rotating handle loom which is adapted to mate with
one of two surfaces similarly provided on the non-rotatable,
supporting member. Thus, when the handle loom is rotated by the
oarsman in the usual fashion during the power and return strokes,
the mating surface on the handle loom engages one of the surfaces
on the non-rotatable member positioning the blade in either a
generally normal or parallel plane with respect to the water. The
converse is true when the handle loom is again rotated by the
oarsman to position the mating surface so that it engages the other
surface on the non-rotatable member.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in greater detail with
particular reference to the accompanying drawings wherein like
reference numerals refer to the same or similar parts and
wherein:
FIG. 1 is a plan view of a boat equipped with a forwards facing
rowing apparatus according to the invention;
FIG. 2 is a side elevational view of the forwards facing rowing
apparatus shown in FIG. 1;
FIG. 3 is a view similar to FIG. 2 but showing parts of the rowing
apparatus in exploded detail;
FIG. 4 is a plan view of the rowing apparatus illustrated in FIGS.
1-3, showing both the handle and blade looms and a set of swing
gears used as a coupling device for feathering the oar blade
according to a preferred embodiment of the invention;
FIG. 5 is a plan view of the rowing apparatus taken along the line
5--5 in FIG. 2;
FIG. 6 is a side elevational view of the rowing apparatus of FIG. 1
taken from the stern of the boat hull and with the swing gears
removed in order to show in greater detail the handle and blade
loom sweep hinge members co-axially mounted onto the oarlock
mainframe via a single sweep hinge pin;
FIG. 7 is an enlarged plan view of the entire oarlock assembly
shown in FIG. 1;
FIG. 8 is an enlarged side elevational view of the oarlock assembly
looking inward from the right side in FIG. 7;
FIG. 9 is an enlarged plan view of the outrigger, oarlock mainframe
and teeter hinge members for mounting the oarlock assembly shown in
FIGS. 7 and 8;
FIGS. 10 and 11 are plan views similar to FIG. 1 showing the
forward and aft positions of a linkage mechanism used to
synchronize movement of the handle and blade looms during the
rowing operation;
FIG. 12 is an elevational view of a hinge assembly for connecting
one arm of the linkage mechanism to the handle or blade loom;
FIG. 13 is a side elevational view of the entire linkage mechanism
shown in FIGS. 10 and 11;
FIG. 14 is a cross sectional view of a universal type hinge
assembly used in the linkage mechanism shown in 15 FIG. 13;
FIG. 15 is an elevational view of a modified swing gear for use in
the rowing apparatus of the invention;
FIGS. 16 and 17 are plan views similar to FIG. 4 showing the fore
and aft positions of the handle and blade looms in a rowing
apparatus employing the modified swing gear shown in FIG. 15;
FIG. 18 is a plan view of a boat and a forwards facing rowing
apparatus employing another linkage mechanism according to another
embodiment of the invention;
FIG. 19 is an enlarged plan view of the linkage mechanism shown in
FIG. 18;
FIG. 20 is a side elevational view of the linkage mechanism shown
in FIG. 19;
FIG. 21 is a plan view similar to FIG. 4 showing an oarlock
assembly employing a single universal joint as a coupling device
for feathering the oar blade according to another embodiment of the
invention;
FIG. 22 is a side elevational view of the oarlock assembly shown in
FIG. 21;
FIG. 23 is an enlarged side elevational view of part of the oarlock
assembly shown in FIG. 22;
FIG. 24 is a plan view similar to FIG. 4 showing an oarlock
assembly employing double universal and splined slip joints as a
coupling device according to still another embodiment of the
invention;
FIG. 25 is a side elevational view of the oarlock assembly shown in
FIG. 24;
FIG. 26 is a plan view similar to FIG. 4 showing an oarlock
assembly employing a walking beam with connecting link rods as a
coupling device according to still another embodiment of the
invention;
FIG. 27 is a side elevational view of the oarlock assembly shown in
FIG. 26;
FIG. 28 is a plan view similar to FIG. 4 showing an oarlock
assembly employing levers with a connecting push-pull wire cable as
a coupling device according to yet another embodiment of the
invention;
FIG. 29 is a side elevational view of the oarlock assembly shown in
FIG. 28;
FIG. 30 is a side elevational view of a rotatable blade loom
assembly employed in a rowing apparatus according to another
embodiment of the invention;
FIG. 31 is a similar view of a rotatable handle loom assembly
employed in a rowing apparatus according to an embodiment of the
invention similar to that shown in FIG. 30;
FIG. 32 is a cross-sectional view of the handle loom assembly taken
along the line 32--32 in FIG. 31;
FIG. 33 is a similar view of the handle loom assembly taken along
the line 33--33 in FIG. 31;
FIG. 34 is a cross-sectional view of part of a non-rotatable,
tubular casing for supporting the rotatable handle loom showing the
sweep hinge member for mounting the assembly along the common sweep
axis; and
FIG. 35 is a perspective view of a combined sweep hinge member and
bracket for mounting the handle loom assemble shown in FIG. 31.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The general arrangement of a boat or shell equipped, with a
forwards facing rowing apparatus according to a preferred
embodiment of the invention is shown in FIGS. 1-14 wherein the
numeral 10 is a boat hull having fore and aft ends 11, 12,
respectively, and 13 is one of a pair of outriggers extending
laterally outward from each side of the hull. Although only one of
the outriggers is shown in the drawing along with its associated
rowing apparatus for purposes of simplicity, it will be understood
that both outriggers and the rowing apparatus are identical in
construction and design.
An oarlock mainframe 14 having a pair of teeter hinge members 15,
16 is mounted to the outer end of the outrigger 13. As best shown
in FIGS. 2, 3 and 8, the outrigger 13 has a pair of outwardly
extending, spaced apart teeter hinge members 17, 18 which mate with
the teeter hinge members 15, 16 on the oarlock mainframe 14. A
teeter hinge pin 19 having a threaded outer end 20 passes through
the mating teeter hinge members 15, 17 and 16, 18, respectively,
and is locked in place by a fastener 21. The oarlock mainframe 14
is rotatable about the axis of the teeter hinge pin 19 which
extends in a generally horizontal direction fore and aft of the
boat hull 10.
An articulated oar loom assembly indicated generally at 22 is
mounted onto the rotatable oarlock mainframe 14. As best shown in
FIG. 1, the oar loom assembly includes an elongated handle loom 24
having an in-board end 25 and an outboard end 26 and an elongated
blade loom 27 having an inner end 28 and an outer end 29. A handle
or grip 30 is rotatably mounted to the in-board end 25 of the
handle loom 24 and a blade 31 is rotatable mounted to the outer end
29 of the blade loom 27.
The handle loom 24 has affixed to its out-board end 26 a sweep
hinge member 32 (FIG. 6). Similarly, the blade loom 27 has affixed
to its inner end 28 a sweep hinge member 34. The preferred sweep
hinge members 32, 34 are generally L-shaped in configuration, each
having a circular base portion 35, 36 (FIG. 5) at its lower end and
an outwardly extending tubular sleeve 37, 38 at its upper end. The
base portions 35, 36 have central apertures 39, 40 (FIG. 3) and
flat sides which serve as bearing surfaces. The tubular sleeves 37,
38 are disposed generally tangential to the circular base portions
35, 36 and are of such size to fit snugly around the ends of the
handle and blade looms 24, 27.
As best shown in FIGS. 3 and 6, the handle and blade looms 24, 27
are rotatably mounted to the oarlock mainframe 14 via the two sweep
hinge members 32, 34 and a single sweep hinge pin 42. The hinge pin
42 extends through an aperture 43 in the oarlock mainframe 14 (FIG.
9), passes co-axially through the apertures 39, 40 in the sweep
hinge members 32, 34 and is secured at its outer end by a fastener
44 (FIG. 3). It will be seen by this arrangement that both the
handle loom 24 and the blade loom 27 are rockable about the
generally horizontal axis of the teeter hinge pin 19 and are also
rotatable about a common generally vertical axis 45 extending
through the sweep hinge pin 42. It will also be seen that by
mounting the ends of the handle and blade looms 24, 27 in
substantially tangential arrangement with respect to the sweep
hinge members 32, 34, space is provided directly above the hinge
pin 42 to accommodate a coupling means for feathering the blade 31
during the return stroke of the rowing cycle as shall be described
hereinafter in greater detail.
In the embodiment of the invention illustrated in FIGS. 1-14, an
elongated torque shaft 47 is mounted within a longitudinal bore 48
(FIG. 7) extending axially from the outboard end 26 to the in-board
end 25 of the handle loom 24 where one end of the shaft 47 is
affixed to the handle 30. Similarly, an elongated torque shaft 49
(FIG. 8) is mounted within a longitudinal bore 50 extending axially
from the inner end 28 to the outer end 29 (FIG. 7) of the blade
loom 27 where one end of the shaft 49 is affixed to the blade 31.
At its opposite end, the torque shaft 47 extends a short distance
beyond the handle loom 24 into the space 46 provided above the
sweep hinge pin 42 (FIG. 8), while the other torque shaft 49
extends a short distance beyond the blade loom 27 also into the
space 46, both ends of the shafts being orientated in a generally
tangential relation to the pair of co-axial mounted sweep hinge
members 32, 34.
A swing gear 51 is affixed to the end of the torque shaft 47 in the
space 46 and is rotatable together with the handle 30. Similarly, a
swing gear 52 is affixed to the end of the torque shaft 49 in the
space 46 and is rotatable together with the blade 31. The swing
gears 51, 52 are arranged to engage one another at variable sweep
angles with the tangent line of the gear pitch circle of each swing
gear aligned with the common sweep hinge axis 45 extending through
the sweep hinge pin 42 as best shown in FIGS. 7 and 8. This
arrangement of the swing gears 51, 52 is very important since it
allows the gears to remain in mesh regardless of the large and
rapid changes in angularity that occur between the handle and blade
looms 24, 27 during the sweep action of rowing.
During the return stroke of the blade loom 27, the blade 31 can be
easily feathered to a position substantially parallel to the
surface of the water by simply rotating the handle 30. Conversely,
by rotating the handle 30 in the opposite direction, the blade 31
can be changed to a position substantially normal to the surface of
the water during the power stroke. The motion of the handle 30 is
transferred directly to the blade 31 through the two torque shafts
47, 49 via the coupling arrangement employing the two swing gears
51, 52. The use of the swing gears 51, 52 has many advantages in
this embodiment of the rowing apparatus. A major advantage is that
the swing gears reverse the rotation of feathering at the blade 31
from that at the handle 30. Thus, the oarsman is able to employ the
conventional method of feathering used in rearwards facing rowing,
that is, by lowering his wrist during the return stroke. As pointed
out above, this is highly desirable in the case of forward facing
rowing. Moreover, swing gears have a very low friction and reduce
oarsman's fatigue brought on by feathering. Of course, as pointed
out above, swing gears can easily accommodate large angle changes
between the axes of the gears.
Referring specifically to FIGS. 1, 10 and 11, a linkage assembly
indicated generally at 54 is provided for synchronizing the motion
of the handle loom 24 and the blade loom 27. The linkage includes a
first link rod 55 connected near one end to the handle loom 24 and
a second link rod 56 connected near one end to the blade loom 27.
The first link rod 55 is connected to the side of the handle loom
24 facing the fore end of the boat hull 10 by a vertical hinge pin
57 (FIG. 12), the rod 55 being shown overlying the handle loom 24
but it can of course underlie the handle loom as well. The second
link rod 56 is connected to the aft side of the blade loom 27 by a
similar bi-directional vertical hinge pin 58. In the embodiment of
the linkage assembly illustrated, the two link rods 55, 56 are
connected to the handle and blade looms 24, 27 at about an equal
distance along their lengths from the common sweep hinge pin 42 and
are connected to one another at their opposite ends by a common,
floating, vertical hinge pin 59. A third link rod 60 is connected
at one end to both the first and second link rods 55, 56 using the
same common hinge pin 59, the opposite end of the third link rod 60
being connected at a fixed point on either the boat hull 10 or the
outrigger 13. The hinge pin assemblies for connecting the two ends
of the third link rod 60 are different from those employed to
connect the link rods to the handle and blade looms 24, 27, that
is, the hinge pin assemblies are of the universal type as more
clearly shown in FIGS. 13 and 14. For example, the common hinge pin
59 used for connecting one end of the third link rod 60 to the
opposite ends of the first and second link rods 55, 56 extends
through a spherical bearing 61 which is rotatably mounted inside a
spherical aperture 62 located at the end of the link rod 60. The
hinge pin assembly at the opposite end of the link rod 60 is
identical except that a hinge pin 63 is used to connect the link
rod to a bracket 64 mounted, for example, to the boat hull 10.
It will be seen by reference particularly to FIGS. 10 and 11 that
the linkage assembly 54 serves to synchronize the motion of the
handle and blade looms 24, 27 during the rowing operation. The
oarsman sits on the seat 65 with his feet secured to the footrest
66 and facing forward toward the fore end 11 of the boat hull 10.
When the oarsman pulls the handle loom 24 (FIG. 10) rearwardly
toward the aft end 12, the blade loom 27 is forced to move in the
same direction as that of the handle loom 24, that is, rearwardly
toward the aft end 12 as shown in FIG. 11. Conversely, during the
return stroke, the oarsman pushes the handle loom 24 in the
opposite direction and the blade loom 27 is forced to move in the
same direction as that of the handle loom 24, that is, toward the
fore end 11 of the boat hull 10. At the same time, it will be seen
that the universal hinge pin assemblies including the two spherical
bearings 61 rotatably mounted at opposite ends of the third link
rod 60 allow the oarlooms to teeter or rock about the horizontal
axis of the teeter hinge pin 19. Thus, during the power stroke as
seen in FIGS. 10 and 11, the oarsman raises the handle loom 24 to
lower the blade 31 into the water at the beginning of the stroke,
while during the return stroke, the oarsman lowers the handle loom
24 in order to raise the blade 31 out of the water until the rowing
cycle has been completed.
In FIGS. 16 and 17, there is shown a modification of the rowing
apparatus just described wherein each swing gear 51, 52 is
approximately a quarter sector (FIG. 15) of a full gear circle,
leaving additional room to accommodate the ends of the torque
shafts 47, 49 within the space 46. Since only a quarter sector of
the gear is required to feather the blade 31 through an angle of 90
degrees, the remaining portion of the gear circle can be eliminated
without affecting operation of the swing gears, thereby increasing
the sweep angle of both the handle and blade looms 24, 27.
FIGS. 18-20 show a different embodiment of the rowing apparatus
wherein the linkage assembly 54 of FIG. 1 used to synchronize the
motion of the handle and blade looms 24, 27 is replaced by a track
and slider arrangement indicated generally at 67. As shown, this
track and slider arrangement includes a first link rod 68 hingeably
connected at one end to the handle loom 24, a second link rod 69
hingeably connected at one end to the blade loom 27, the opposite
ends of the first and second link rods 68, 69 being hingeably
connected together and to a slider 70 via a hinge pin 72. The
slider 70 is movably mounted onto an elongated track 71 which is
fixedly secured at one end to the oarlock mainframe 14 as shown in
FIGS. 19 and 20 and which is orientated generally fore and aft of
the boat hull 10. The two link rods 68, 69 are generally of equal
length and are attached to the handle and blade looms 24, 27 using
the same bi-directional hinges described hereinabove at points
substantially equi-distant from the sweep hinge pin 42. It will be
seen that this track and slider arrangement operates in basically
the same manner as the linkage assembly 54 of FIG. 1, the link rods
68, 69 forcing the handle and blade looms 24, 27 to move together
in the same direction during the sweep action of rowing.
Also in the embodiment of the rowing apparatus shown in FIG. 18,
the co-axially mounted torque shafts 47, 49 are replaced by
external torque shafts 75, 76 rotatably mounted alongside the
handle and the blade looms 24, 27. The torque shaft 75 is located
on the aft side of the handle loom 24 while the torque shaft 76 is
located on the fore side of the blade loom 27. This construction
also allows the use of swing gears 77, 78 mounted to the ends of
the torque shafts 75, 76, the swing gears being similarly arranged
to engage one another such that the tangent line of the pitch gear
circle of each gear is aligned with the sweep hinge axis 73. It
will be understood, of course, that the shafts 75, 76 may also be
mounted onto opposite sides of the handle and blade looms 24, 27 as
will readily occur to those skilled in the art.
An important feature of the linkage assemblies 54, 67 illustrated
in FIG. 1 and FIGS. 18-20, respectively, is the ability to set the
linkages to different linkage ratios between the handle loom and
the blade loom to speed up (or slow down) the blade sweep motion.
In conventional rowing during the power or propulsion stroke, the
oarsman is accelerating the mass of his body forwards in the boat
while the propulsion of the blades accelerates the boat hull
forwards at the same time. However, in forwards facing rowing, the
oarsman's body is accelerating aft while the boat hull is
accelerating forwards. This produces less "feel" of pulling on the
propulsion stroke and a more negative pulling at the feet in the
laced shoes. The result feels like a two-speed bike in too low a
gear. To avoid this, the linkage ratio between the handle loom and
the blade loom can be adjusted to produce a faster sweep of the
blade loom than the handle loom. Thus, instead of having the two
link rods 68, 69 in FIG. 18, for example, of generally equal length
and attached to the handle and blade looms 24, 27 at points
substantially equi-distant from the sweep hinge pin 42, the link
rods can be attached at unequal distances from the sweep hinge pin
42 to attain either a faster or slower sweep motion of the blade
loom.
FIGS. 21-23 show another embodiment of the invention wherein the
swing gears 51, 52 are replaced by a single universal coupling
indicated generally at 79. As shown, the universal coupling
includes a yoke 80 affixed to the end of one of the torque shafts,
in this case the shaft 47 mounted co-axially within the handle loom
24. A yoke 81 is affixed to the end of the other torque shaft 49
and is connected to the yoke 80 via a hinge block 82 and a pair of
hinge pins 83, 84. The hinge pins 83, 84 extend through the block
82 at substantially right angles to one another as best shown in
FIG. 23. The two yokes 80, 81 and the hinge block 82 are centered
generally about the common sweep hinge axis 42 (see FIG. 22). This
arrangement, however, does not reverse the rotation of feathering
at the blade from that at the handle as in the case of the swing
gears.
A somewhat similar embodiment of the invention is shown in FIGS. 24
and 25. Here, the coupling arrangement indicated generally at 86
includes a pair of Carden type universal joints, a first joint
including a yoke 87 attached to the end of the torque shaft 47 and
a yoke 88 attached to the end of the torque shaft 49. The first
joint includes a mating yoke 89 affixed to the yoke 87 via a hinge
block 90 and two hinge pins 91, 92. The second joint includes a
mating yoke 94 affixed to the yoke 88 via a hinge block 95 and two
hinge pins 96, 97. As in the previous embodiment, the hinge pins
extend through the hinge block at substantial right angles to one
another. The two mating yokes 89, 94 form a splined slip joint 98
at their opposite ends, one of the yokes 94 having a hollow end and
the other yoke 89 being of a lesser diameter so as to slideably fit
inside the hollow end of the yoke 94. This arrangement has the
advantage over the previous arrangement in that the two universal
joints are able to accommodate a much larger angular displacement
of the handle and blade looms 24, 27. Moreover, the splined slip
joint is able to transmit motion from the torque shaft 47 to the
torque shaft 49 and to accommodate changes in the universal joint
spacing due to the angular sweep arc of each oar loom. However,
rotation of the blade 31 is in the same direction as that of the
handle 30 with this arrangement.
FIGS. 26 and 27 show still another embodiment of the of the
invention wherein the pair of swing gears 51, 52 are replaced by a
coupling mechanism including a walking beam and linkage arrangement
indicated generally at 100. A rocker arm 101 is pivotally mounted
at its center to the upper end of a somewhat longer sweep hinge pin
42. A first lever 102 is affixed at one end to the torque shaft 47
in the handle loom 24 and a second lever 103 is affixed at one end
to the torque shaft 49 in the blade loom 27. A first link rod 104
is then connected between the outer end of the first lever 102 and
one end of the rocker arm 101. A second link rod 105 is connected
between the outer end of the second lever 103 and the opposite end
of the rocker arm 101. It will be seen that any motion of the
torque shaft 47 caused by turning the handle 30 is transferred
directly to the rocker arm 101 via the first lever 102 and link rod
104, causing the rocker arm to rotate in either the clockwise or
counterclockwise direction. This motion in turn is transferred to
the shaft 47 via the second lever 103 and link rod 105, rotation of
the shaft 49 and the blade loom 27 being in the same direction as
the shaft 47 and the handle loom 24. It should also be noted in
this arrangement that the rocker arm 101 is rotatable along with
the hinge pin 42 about the common sweep axis 45 and thus permits
both oarlooms to move through large sweep angles without
interfering with the feathering action.
In FIGS. 28 and 29, there is shown still another embodiment of the
invention wherein the pair of swing gears 51, 52 are replaced by a
similar push-pull linkage assembly indicated generally 106. This
linkage assembly includes a first lever 107 connected to the torque
shaft 47 in the handle loom 24 and a second lever 108 connected to
the torque shaft 49 in the blade loom 27. A push-pull flexible wire
109 enclosed inside a flexible casing 110 is provided and has one
end connected to the outer end of the first lever 107 and its
opposite end connected to the outer end of the second lever 108.
The two sweep hinge members 32, 34 are modified to include in this
embodiment a pair of generally L-shaped arms 111, 112 which extend
upwardly beyond the tubular sleeves 37, 38, respectively. The arms
111, 112 are disposed radially inward toward the common sweep hinge
axis 45 and secure the opposite ends of the flexible casing 110
against axial movement along the wire 109. It will be seen that any
motion of the torque shaft 47 caused by turning the handle 30 is
transferred directly to the push-pull wire 109 via the first lever
107 causing the second lever 108 and in turn the shaft 49 and blade
31 to move in the same direction as the shaft 47.
In all of the embodiments of the rowing apparatus described
hereinabove, the handle and blade loom are non-rotatable members
and a rotatable member, such as a torque shaft, extends along each
one of the oarloom members, the handle being affixed to one torque
shaft and the blade being affixed to the other torque shaft. FIGS.
30-35, inclusive, show different embodiments of the rowing
apparatus according to the invention wherein at least one of the
handle or blade loom is a rotatable member and wherein a
non-rotatable member is provided for supporting the rotatable
handle and/or blade loom, the handle in this case being affixed to
and rotatable with the handle loom and the blade being affixed to
and rotatable with the blade loom.
FIG. 30, for example, shows a blade loom assembly, generally
indicated at 114, which includes an elongated, rotatable blade loom
115 having a blade 116 affixed to its outer end and a swing gear
117 affixed to its inner end. The blade loom 115 is rotatably
supported inside a non-rotatable, tubular casing 118 which serves
as a bearing housing. Preferably, the tubular casing 118 extends
along the blade loom 115 from its inner end to about one-third or
less of its length. The casing 118 is affixed at one end via a
bracket 120 to one of the sweep hinge members 121 which is mounted
about the common sweep hinge axis 122. An annular bearing 123, such
as a roller bearing, is mounted inside one end of the tubular
casing 118. Similarly, an annular bearing 124 is mounted inside the
opposite end of the casing 118. The bearings 123, 124 allow for
free rotation of the elongated handle loom 115 within the tubular
casing 118.
An important feature of the rotatable blade loom assembly described
hereinabove is that all of the moveable parts, such as the roller
bearings, which would normally be made of corrodible metals, are
not directly exposed to the water during the rowing operation and,
therefore, are not required to be sealed.
FIG. 31 shows a handle loom assembly, generally indicated at 125,
which includes an elongated rotatable handle loom 126 having a
handle 127 affixed to its inner end and a swing gear 128 (shown
here as a swing gear sector similar to that shown in FIG. 15)
affixed to its outer end. The swing gear 128 is connected to a
short extension shaft 130 which is connected in turn to the handle
loom 126 via a universal joint generally indicated at 129. The
shaft 130 extends co-axially into a blind hole or bore 131 which is
drilled into the outer end of the handle loom 126. The short shaft
130 is joined to the handle loom 126 via a universal pin and slot
arrangement as shown in FIG. 32. The drive pin 132 passes through
the shaft 130 and is disposed inside a driven slot 133 provided in
the mating member, that is, the drilled end of the handle loom 126.
The drive pin 132 can also be placed in the end of the handle loom
while the slot is provided in the short shaft 130.
The handle loom 126 is rotatably mounted inside a nonrotatable,
tubular casing 134 which also serves as a bearing housing.
Preferably, the tubular casing 134 extends along the handle loom
126 from its outer end to about one-third or less of its length.
The casing 134 is affixed at one end to one of the sweep hinge
members 135 via a bracket 136 as shown more particularly in FIGS.
31 and 34. The bracket 136 is shaped with an arcuate section 137
for receiving the cylindrical wall portion of the tubular casing
134 as shown in FIG. 35. The casing 134 is welded or otherwise
secured to the bracket 136 which is in turn welded or otherwise
secured to the sweep hinge member 135.
An inner tubular sleeve 138 is mounted inside the tubular casing
134 at its end adjacent to the outer end of the handle loom 126.
The handle loom 126 is shaped with an enlarged outer end as shown
at 139 which fits rotationally within the inner sleeve 138. An
annular bearing 140, such as a double ball bearing, is mounted
inside the outer end of the tubular sleeve 138 and allows for
alignment and free rotation of the shaft 130 affixed to the swing
gear 128.
The handle loom 126 is formed with an annular embossment 142 which
is located just short of the point where the handle loom 126
extends beyond the opposite end of the tubular casing 134 as best
shown in FIG. 31. The annular embossment 142 has an outer diameter
which is less than the inner diameter of the tubular casing 134
providing a clearance 143 therebetween which enables the handle
loom 126 to move laterally within the casing.
As best shown in FIG. 33, the tubular casing 134 is provided with
two flat surfaces 144, 145 on its interior wall within the same
opposite end of the casing. The two flat surfaces are arranged
perpendicular to one another, one of the flat surfaces 144 being
disposed vertically while the other flat surface 145 is disposed
horizontally with respect to the surface of the water. The annular
embossment 142 on the handle loom 126 is similarly provided with a
single flat surface 146 which is adapted to engage either one of
the flat surfaces 144 or 145 on the casing 134 depending on the
angular position of the rotatable handle loom 126. It will be seen
then that during the power stroke, the oarsman can easily position
the blade at an angle that is normal to the surface of the water by
simply placing the flat surface 146 on the embossment 142 against
the vertically arranged flat surface 144 on the casing 134 and,
conversely, the oarsman can feather the blade at a generally
horizontal angle with respect to the surface of the water by simply
rotating the handle loom 126 to place the flat surface 146 against
the horizontally arranged flat surface 145. The oarsman can
actually "feel" the flat surface 146 engaging either of the flat
surfaces 144, 145 as he drops and raises his wrist to rotate the
handle 127 during both the power and feathering strokes. This is a
considerable advantage to the oarsman during competitive rowing
since he is not required to actually look at both blades to
determine their attitude which might otherwise distract him from
his rowing efforts.
It should be noted that the rotatable blade and handle loom
assemblies 114, 125 shown in FIGS. 30 and 31-35, respectively, can
be employed together with one another to constitute a single
oarloom assembly or, alternatively, either one of the rotatable
blade or handle looms may be employed with any one of the
non-rotatable handle or blade looms illustrated in the previous
embodiments. The same is also true in the case of the various
coupling devices disclosed herein which can be employed to replace
either of the swing gears 117 or 128 shown in FIGS. 30 or 31,
respectively.
* * * * *